Buggy code:
public class MainGui extends JFrame { public MainGui ( ) { } @ SuppressWarnings ( "unchecked" ) private void initComponents ( ) { } private void fieldLoadActionPerformed ( ActionEvent evt ) { } private void fieldSaveActionPerformed ( ActionEvent evt ) { } private void menuExitActionPerformed ( ActionEvent evt ) { } private void buttonCompileMouseClicked ( MouseEvent evt ) { } private void buttonCompileActionPerformed ( ActionEvent evt ) { } private void menuAboutActionPerformed ( ActionEvent evt ) { } private void buttonLoadActionPerformed ( ActionEvent evt ) { } private void buttonSaveActionPerformed ( ActionEvent evt ) { } private void menuLoadPlatActionPerformed ( ActionEvent evt ) { } private void buttonRunMouseClicked ( MouseEvent evt ) { } private void buttonRunActionPerformed ( ActionEvent evt ) { try { String input = fieldInput . getText ( ) ; printLog ( "Got<seq2seq4repair_space>input.<seq2seq4repair_space>Running...\n\n" ) ; printLog ( "" ) ; SourceOutput so = Source . execute ( new SourceOptions ( input , ( ( String ) ( choicePlatform . getModel ( ) . getSelectedItem ( ) ) ) , false ) . setFiles ( new File ( "BenchData//assets" ) , new File ( "BenchData//src" ) , null ) ) ; printLog ( so . operationLog ) ; if ( ! ( so . dets . isEmpty ( ) ) ) { if ( boxShowErrors . isSelected ( ) ) { fieldOutput . setText ( ( "There<seq2seq4repair_space>were<seq2seq4repair_space>errors<seq2seq4repair_space>found:\n\t" + ( so . errMsgs . replace ( "\n" , "\n\t" ) ) ) ) ; } else { StringBuilder sb2 = new StringBuilder ( ) ; sb2 . append ( "There<seq2seq4repair_space>were<seq2seq4repair_space>errors<seq2seq4repair_space>found:\n" ) ; for ( SourceException err : so . errs ) { sb2 . append ( "\t" ) ; sb2 . append ( err . getMessage ( ) ) ; sb2 . append ( "\n" ) ; } fieldOutput . setText ( sb2 . toString ( ) ) ; } } else { <START_BUG> fieldOutput . setText ( so . output . getOutputString ( ) ) ; <END_BUG> } printLog ( "" ) ; } catch ( Exception ex ) { Logger . getLogger ( MainGui . class . getName ( ) ) . log ( Level . SEVERE , null , ex ) ; fieldOutput . setText ( "An<seq2seq4repair_space>unknown<seq2seq4repair_space>error<seq2seq4repair_space>occured." ) ; } } private void choicePlatformActionPerformed ( ActionEvent evt ) { } private JCheckBox boxShowErrors ; private JButton buttonCompile ; private JButton buttonLoad ; private JButton buttonRun ; private JButton buttonSave ; private JComboBox choicePlatform ; private JTextPane fieldInput ; private JTextField fieldLoad ; private JTextPane fieldLog ; private JTextPane fieldOutput ; private JTextField fieldSave ; private JLabel jLabel1 ; private JMenuBar jMenuBar1 ; private JPanel jPanel1 ; private JPanel jPanel2 ; private JPanel jPanel3 ; private JPanel jPanel4 ; private JPanel jPanel6 ; private JScrollPane jScrollPane1 ; private JScrollPane jScrollPane2 ; private JScrollPane jScrollPane4 ; private JTabbedPane jTabbedPane2 ; private JMenuItem menuAbout ; private JMenuItem menuExit ; private JMenu menuFile ; private JMenu menuHelp ; private JMenuItem menuLoadPlat ; public void printLog ( Object text ) { } public void printErrors ( ArrayList < SourceException > a ) { } }

Fix:
fieldOutput . setText ( "Done." ) ;